22 February 2010

Man and his machine. The machine: an ancient Ferguson that has until recently lain dormant in a barn, for over twenty years. Note the highly original use of an old axle stand to connect the collector from the engine manifold to a DTM back box and twin upturned exhausts. The man: Geoff Lowe.

The third area of limestone extraction very close to home is that of Crickheath Hill, which is riddled by quarries of the smaller sort, heavily blanketed in hart's tongue ferns and ivy, and which reward careful exploration. There are dilapidated quarrying buildings and partially blocked adits to be found, and the area is rich with wildlife, which benefits from the various pools that form between the quarry faces and spoil heaps. There is much evidence of badgers (Meles meles) - setts, latrines, and even a skull, evincing the typically pronounced saggital crest to which are anchored the powerful jaw muscles.

20 February 2010

At the foot of Llanymynech Hill is the Llanymynech Heritage Area, the most notable feature of which is the Hoffman kiln, one of only four remaining in Britain. The others are at Armadale, West Lothian; Carluke, Lanarkshire; Langcliffe, North Yorkshire; and Minera, near Wrexham.

Traditionally, limestone was burnt in draw kilns such as those pictured above, on the hill, wherein layers of stone and coal were loaded from the top and the resulting lime drawn from the bottom. From time to time operations had to be suspended in order to clear from the chamber any 'unburnt' stone. The Hoffman kiln, by contrast, was operated on a constant basis, using a continuous tunnel divided into a number of chambers. In such kilns, the fire can burn without surcease for years. The design was developed in Germany by Friedrich Hoffman, who first patented it in 1857 for the firing of bricks. Early Hoffman kilns were circular, but later versions were elliptical or rectangular, which enabled them to have more chambers.

The Llanymynech kiln, built in about 1899 of brick in battered section, had 14 chambers. At any one time one chamber was empty, one was being filled, five were pre-heating, two were firing, four were cooling, and one was being emptied. The limestone was brought alongside the kiln on the tramways that ran down from the quarries above, and stacked within the chambers in temporary walls. Between these were left gaps aligned with the numerous coal feed holes in the tunnel roof. The coal was brought straight from the nearby railway siding onto the kiln's roof, again by tramway.

Once a chamber had been loaded, its entrance was temporarily sealed with stacked bricks. Coal was fed from above into the spaces between the limestone stacks, and burned in the hot air that circulated from one chamber to the next, drawn down into and along the central flue that leads to the 140 foot chimney. This circulation was controlled by using the flues and dampers alongside each chamber entrance. Once the lime in one chamber was properly burned, the flue was closed and coal was fed into the next chamber, the flue for which was opened, and so on round the ring. Given the caustic nature of lime, and the need to keep out the damp, the kiln was covered with a corrugated iron roof. This has been reinstated, in mild steel, as part of a sensitive and informative restoration.

Hoffman kilns are still used in 'developing' countries; in Iran there are kilns that have been working continuously for 35 years. That at Llanymynech continued in use only until the outbreak of WWI, in 1914. The introduction of chemical fertilizers, and the reduction in the use of lime mortar, made production of lime uneconomic.

19 February 2010

Between Wem and Whitchurch is the widely spread village of Whixall. It is, despite its small population, one of the largest parishes in England. Water defines the place, that in the Shropshire Union Canal, on which lies Whixall Marina, and that in the surrounding mosses. Together, the Fenn's, Whixall, Bettisfield, Wem and Cadney Mosses form Britain's third largest lowland peat bog, and are home to a wide range of acid-tolerant flora, including 92 mosses and liverworts. Funghi addicts come here in autumn to hunt edible mushrooms. The back lanes are punctuated by numerous farmyards, each of which seems to be home to an interesting old tractor, truck or piece of 'junk.'

In 1643, during the English Civil War, 40 Roundheads successfully defended the town of Wem from as many as 5,000 Cavaliers, not the last time that a small number of parliamentarians screwed a much greater quantity of the populace. Wem was severely damaged by fire in 1677, and doesn't look like it's ever quite recovered.
Its faded feel is pleasant though, and there are plenty of architectural details to observe, given the wide range of building materials used - principally red sandstone, brick and timber. Wem is definitely a town that rewards those who habitually look above often ugly modern shop fronts. It's a shame that more Victorian display windows, such as the round cornered one in the high street here, aren't preserved in our towns.

Wem was home to the essayist William Hazlitt but is probably most famous for its annual Sweet Pea Show, which celebrates the town's connection with Lathyrus odoratus through Henry Eckford, who in the nineteenth century developed over an hundred hybrids of the plant.

09 February 2010

Criggion Radio Station, callsign GBZ, was operated by the Post Office and, after privatisation of telecommunications in 1984, British Telecom. It passed coded Admiralty, and later Ministry of Defence, instructions to the Navy's ships and submarines, including those carrying Trident. During WWII, Criggion played its part in the sinking of the battleships Scharnhorst and Bismarck, and the capture of the tanker Altmark. During the Cold War the site was a Category A target for the Soviet Union. It was likely the channel by which Margaret Thatcher's 1982 instruction to sink the General Belgrano was passed.

Criggion was planned in 1940 as a back-up to the station at Rugby, as there were concerns that the latter could be damaged by stray bombs intended for Coventry. When built, it consisted of two high frequency (HF) stations, a low frequency (LF) station, and a very low frequency (VLF) station, spread out across what used to be a 400 acre site. The site was chosen because steel was in short supply at the time, and only three 680 foot pylons could be found, originally bound for the Trincomalee naval station, Ceylon (now Sri Lanka). A steep hill next to level ground to provide the fourth and fifth anchorages for the VLF aerial was required. Breidden Hill, at about 900 feet, was perfect for this, and the nearby Severn could provide water for the heat exchangers used to cool all the valves.

Building commenced in 1941. The first HF transmitter was operational by September 1942. Whilst still being tested, in early 1943, the VLF transmitter at Criggion had to be hastily commissioned to take over from Rugby, whose similar transmitter had been damaged by fire (it was out of action for six months). Additional HF transmitters were installed between 1943 and 1945. The military facilities were further added to during the Cold War. A larger VLF aerial was installed in 1967-68, slung from 720 feet stayed masts, the concrete blocks to support which can still be seen.

The station also carried civilian traffic. Until the Atlantic cable was laid, Criggion carried all telephone circuits to America. As cables and satellites proliferated, the various HF facilities were dispensed with, and all 25 HF transmitters and their associated aerials were decommissioned by 1971-72. The facilities were upgraded in 1983 and as recently as 1991, the VLF and three LF transmitters continuing in service until 31 March 2003. The pylons and masts for the VLF and LF aerials were brought down with explosives within months of the site's closure.

The buildings are fascinating. Of course, much of the equipment was removed when the site closed, and subsequently the place has been looted, no doubt for the miles of copper cable that it must have contained, but there are clues to its past. The built-up foundations were designed to accommodate the flooding of the Severn. In the early days transport around the site came in the form of a tractor and trailer, but later a DUKW and an amphibious jeep were provided. Garages, a pumping station, and what look like living accommodation provide a feel for how busy the place must have been at its height, when 160 people worked here.

04 February 2010

At the southern end of the ridge that forms Llanymynech, Crickheath and Llynclys hills are a number of abandoned limestone quarries. These would once have resounded with explosions from charges tamped into holes drilled into the rock, which have left their characteristic half cylinders in the cliff-face. Now though the only sounds are from buzzards and peregrine falcons, dripping water and, in the summer, the occasional climber pitting their wits against the repeated tiers of horizontally bedded rock. There are three drum brakes here, one (pictured) at the top of the 'English' inclined plane, a second at the head of the 'Welsh' inclined plane, and a third above the short drop into the massive tunnel cut straight through the hill into a lower-level quarry.

The tunnel is signed as dangerous, and it's easy to see why once inside: blocks of limestone larger than family cars have fallen from the ceiling. Similarly cordoned off is an adit that appears to run straight into the hillside and may, thus, be a copper mine that predates the quarries; and which demands a return visit with a good torch. The inclined planes carried limestone down to the canal and the Hoffman kiln at the foot of the hill. Oddly, the two tramways, operated by different companies, crossed each other just before passing, via separate tunnels, under what is now the A483. Steel sculptures by David Howorth represent rockmen and a brakesman.

03 February 2010

On the western side of Llynclys Hill, deep amongst the rampant ash saplings and mature silver birch, is an Austin A40 van, a restoration project 'in need of some finishing.' Whatever happened to those old-fashioned junk yards, full of toppling stacks of rusting cars, that, as a kid, one used to come across in the woods? No doubt the health and safety paranoiacs now insist that such yards are securely cordoned off behind weld-mesh fencing on dull industrial estates.

Another victim of the British obsession with 'health and safety' is the once-popular practice of locating and cooking wild fungi. The razor strop (Piptoporus betulinus) grows almost exclusively on birch. Unlike the beefsteak fungus, the razor strop - the cut surface of the fruiting body, the visible part of the fungus, was once used in forming the sharpest of razor edges - is inedible (it's not poisonous, just too woody). Dried, the fruiting body can though be used as tinder.

Crickheath and Llynclys hills are peppered with old limestone quarries grown over with ferns, particularly hart's tongue (Phyllitis scolopendrium), ash and silver birch. There are numerous shafts and adits (some of which are off-limits in order to protect the resident bats), and buildings associated with the task of hauling the limestone down to the Montgomery Canal. Along this the limestone was shipped off to be burnt in kilns, thereby producing lime for spreading on acid soils to improve their fertility. Pictured is the winding house for the tramway between Black Bridge quarry and the wharf at Pant.

Len Pugh lives on Llynclys Hill, in a cottage surrounded by a variety of workshops, outbuildings and garages. In the last are stored the numerous Triumph Stags awaiting restoration by his son, Philip. In the first, ankle deep in shavings and sawdust, Len makes superb furniture, largely in oak. Cabinet maker extraordinaire, he can fashion anything one could want, in any style one could imagine. His favourite style is best described as classic Georgian - simple and enduring.

Len is a retiring man, modest about his abilities in the way that only the truly skilled are. The desk is a take on that of Samuel Pepys, in the Pepys Library at Magdalene College, Cambridge; and is made from both through-and-through and quarter-sawn oak, with a glazed cabinet at one end. The chair to go with it Len made from brown oak, wood from a tree lived upon by the beefsteak fungus (Fistulina hepatica), whichdraws its nutrients from, and passes its waste back into, the tree's sapwood. This waste reacts with the tannins in the tree and changes the colour of the oak from pale to dark brown.

This Week's Read

Irritating Saints

"The pleasantest people in the world were the selfish ones who were also kindly, so that in the middle of their selfishness they thought of you and did something for you. Unselfish people who were always eager to do something for you were so irritating ..." Hugh Walpole, 1931, Judith Paris.